Trimmer Pots for OBXA

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Skiroy
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Trimmer Pots for OBXA

Post by Skiroy » Sat Jan 19, 2013 9:31 am

Does anyone know what pots or where to find the trimmer pots for the OBXA initial frequency and also the different ones for say adjusting the PWO?

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synthRodriguez
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Re: Trimmer Pots for OBXA

Post by synthRodriguez » Sat Jan 19, 2013 1:23 pm

See my post here:

http://www.gearslutz.com/board/electron ... parts.html

Don't know if it will answer all your questions, but maybe.

Edit: This might be interesting to you as well.

http://www.gearslutz.com/board/electron ... mages.html

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Re: Trimmer Pots for OBXA

Post by Skiroy » Sun Jan 20, 2013 10:15 pm

Wow your awesome.

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Re: Trimmer Pots for OBXA

Post by Skiroy » Sun Jan 20, 2013 10:54 pm

Is anyone aware of why these voice cards have different caps. Most of mine have the blue ones but I recently bought 2 more that have the orange. Call me crazy but the orange caps sound a little different.




And where did this guy get these trimmers at 1:08 mins?


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Re: Trimmer Pots for OBXA

Post by Don T » Mon Jan 21, 2013 6:02 am

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Last edited by Don T on Mon Feb 04, 2013 7:44 pm, edited 1 time in total.
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Re: Trimmer Pots for OBXA

Post by Skiroy » Mon Jan 21, 2013 6:23 am

Do you know if any of the caps on the motherboard or control board are in the audio circuit? What caps do you use?

I was going to use these on the voice cards
http://www.partsconnexion.com/capacitor ... a_roa.html

But I cant find the right values for 15uf for the mother board.

Also just out of curiosity what are the trimmers in the video?

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Re: Trimmer Pots for OBXA

Post by Skiroy » Mon Jan 21, 2013 6:54 am

Also can anyone tell me what trimmer is responsible for how loud each card is?

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Re: Trimmer Pots for OBXA

Post by Don T » Tue Jan 22, 2013 9:59 am

.....
Last edited by Don T on Mon Feb 04, 2013 7:44 pm, edited 2 times in total.
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Re: Trimmer Pots for OBXA

Post by Skiroy » Wed Jan 23, 2013 12:59 am

You have made a correct assumption. However I just plan on rebuilding the PSU and replacing the 7 caps on each voice card. And I have 2 bad trimmers. After that I plan on taking it to a specialist. And as far as component substituting everything I am considering is based off advice from technicians that are familiar with working on the OBXA. I have no plans on getting myself into to deep but I think its worth it to tackle the most common issues to see where Im at.

I was only going to use the 25V 22uf on the voice cards only which are about the diameter of the Elnas that are on 2 of my cards now,though they are 35V versions. But I will go with the Nichicons you suggested.

I really would like to replace the trimmers with the current form factor though.

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Re: Trimmer Pots for OBXA

Post by Skiroy » Wed Jan 23, 2013 1:15 am

Don T wrote:
Skiroy wrote:Do you know if any of the caps on the motherboard or control board are in the audio circuit? What caps do you use?

I was going to use these on the voice cards
http://www.partsconnexion.com/capacitor ... a_roa.html

But I cant find the right values for 15uf for the mother board.

Also just out of curiosity what are the trimmers in the video?

If you need to replace any electrolytic caps on a voice card, on the upper and lower motherboards, or the upper and lower control boards, I suggest using these: Nichicon PW Series

Difficult to tell exactly which company makes those trimmers in the video, I know of at least 3 companies that use that form factor.
These are the same series I was looking at for the PSU,but they only come in 35V. That would be fine for the 25V caps in the PSU but not for the 50V ones. I was told to go as high as possible for the PSu as far as voltage 50V-63V if possable.

What is you suggestion for the large PSU caps in the OBXA?

Thankx

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Re: Trimmer Pots for OBXA

Post by Don T » Thu Jan 24, 2013 8:03 am

.....
Last edited by Don T on Mon Feb 04, 2013 7:45 pm, edited 1 time in total.
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Re: Trimmer Pots for OBXA

Post by Skiroy » Fri Jan 25, 2013 12:56 am

Yes I did the highest Voltage caps for the 4700uf are 25V which should be okay because the originals are 25V.

But the 3300uf originals are 50V and the link you provided only go to 35V. I read to go atleast the original voltage but higher the better.

Its abummer because these caps look great.

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Re: Trimmer Pots for OBXA

Post by Skiroy » Sat Jan 26, 2013 2:01 am

What ones you suggest for 50V and higher for the 3300uf and 2200uf?

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